This invention relates to a fiber optic light panel and more particularly to an illuminating panel which is extremely thin and capable of providing a very uniform source of light over a wide area.
The invention is particularly applicable for use in digitizing information such as drawings on a sheet of paper. In this application, a light box is required to illuminate the drawings, preferably from behind, but the common light boxes now in use are not satisfactory because the digitizer tablet has to be able to track the cursor/stylus. The cursor has to be typically within 1/2" of the tablet to be read accurately by the tablet. Because of this limited distance, standard light boxes cannot be used to illuminate drawings.
In addition, light boxes used in hospitals and doctors' offices to read x-rays are bulky and therefore limited in where they can be employed. Also, conventional light boxes can not be employed in backlighting applications such as control panels and other instrumentation applications where space is limited and maintenance can be a problem.
To meet some of these requirements, fiber optic technology has been applied to produce light panels. The following United States Patents are illustrative of such devices.
U.S. Pat. No. 3,114,283 shows a light pickup ring with so-called light pickup elements which appear to be optical fibers.
U.S. Pat. No. 3,654,452 illustrates automotive instrument panel illuminated by an electric lamp. Light conducting cables carry the light to the panel.
U.S. Pat. No. 4,128,332 teaches an illuminator for an office copier utilizing a light rod having a source of light at each end.
In U.S. Pat. No. 4,234,907 there is shown a light emitting fabric which relies on optical fibers woven into a pattern. The use of bends and notches in the fibers to deliver the light is inefficient as well as having other drawbacks.
U.S. Pat. No. 4,471,412 teaches a light conducting member with points along its length where the light is emitted.
U.S. Pat. No. 4,567,551 discloses a surface illuminator combining light from different sources to direct the light to an area where required.
U.S. Pat. No. 4,677,473 shows a soldering inspection system for directing light to the soldered part from different angles using optical fibers to deliver the light.
U.S. Pat. No. 4,763,984 teaches the use of clad fiber optic light channels with means such as scattering centers to emit the light through the cladding in selected areas.
None of the above patents teaches or suggests the present invention.